Results

After 26 patients were excluded, 509 were included in the modified intention-to-treat (mITT) population.

198 (91•7%) of 216 patients in the per-protocol population given fidaxomicin achieved clinical cure, compared with 213 (90•6%) of 235 given vancomycin, meeting the criterion for non-inferiority (one-sided 97.5% CI -4.3%).

Non-inferiority was also shown for clinical cure in the mITT population, with 221 (87.7%) of 252 patients given fidaxomicin and 223 (86.8%) of 257 given vancomycin cured (one-sided 97.5% CI -4.9%).

nalyses of the primary endpoint in the mITT population, outcomes in the two treatment groups did not differ significantly; although patients receiving concomitant antibiotics for other infections had a higher cure rate with fidaxomicin (46 [90.2%] of 51) than with vancomycin (33 [73.3%] of 45; p=0.031).

Occurrence of treatment-emergent adverse events did not differ between groups. 20 (7.6%) of 264 patients given at least one dose of fidaxomicin and 17 (6.5%) of 260 given vancomycin died.